| 摘要 |
PROBLEM TO BE SOLVED: To prevent the contamination of a motor by the lubricating oil of the ball bearings of a polygon mirror with simple constitution and to reduce the size, thickness and cost of the motor by applying an adhesive over the entire circumference of at least one end in the fastening part of a shaft and a rotor boss. SOLUTION: The shaft 1 is rotatably fitted to the bore holes of two pieces of the ball bearings 2 and is shrinkage fitted and fixed with a rotor boss 3. The top end of the bore of the rotor boss 3 is provided with a C chamfered part 3a and the adhesive 10 is applied over the entire circumference of the C chamfered part 3a. The adhesives of, for example, a UV curing type and thermosetting type, etc., are used for the adhesive 10 of this case. The adhesive of particularly the UV curing type is more preferable. Then, the rotor boss 3 plays the role of a shielding between the ball bearings 2 and the polygon mirror 4 in the splashing route A passing the rotor boss 3 and a bracket 8 for splashing the lubricating oil of the ball bearings 2. The splashing route 13 where the lubricating oil of the bearings 2 intrudes between the shaft 1 and the rotor boss 3 and jumps out thereof is sealed by the adhesive 10. |
